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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_000_005_443">&nbsp;</a>NAME</h4><blockquote>
getc - get a byte from a stream
</blockquote><h4><a name = "tag_000_005_444">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="stdio.h.html">stdio.h</a>&gt;

int getc(FILE *<i>stream</i>);
</code>
</pre>
</blockquote><h4><a name = "tag_000_005_445">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>getc()</i>
function is equivalent to
<i><a href="fgetc.html">fgetc()</a></i>,
except that if it is implemented as a macro it may evaluate
<i>stream</i>
more than once, so the argument should never be an expression
with side effects.
</blockquote><h4><a name = "tag_000_005_446">&nbsp;</a>RETURN VALUE</h4><blockquote>
Refer to
<i><a href="fgetc.html">fgetc()</a></i>.
</blockquote><h4><a name = "tag_000_005_447">&nbsp;</a>ERRORS</h4><blockquote>
Refer to
<i><a href="fgetc.html">fgetc()</a></i>.
</blockquote><h4><a name = "tag_000_005_448">&nbsp;</a>EXAMPLES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_005_449">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
If the integer value returned by
<i>getc()</i>
is stored into a variable of type
<b>char</b>
and then compared against
the integer constant EOF,
the comparison may never succeed,
because sign-extension of a variable of type
<b>char</b>
on widening to integer is implementation-dependent.
<p>
Because it may be implemented as a macro,
<i>getc()</i>
may treat incorrectly a
<i>stream</i>
argument with side effects.  In particular,
<i>getc</i>(*<i>f</i>++)
will not necessarily work as expected.
Therefore, use of this function should be preceded 
by &quot;#undef getc&quot; in such situations; 
<i><a href="fgetc.html">fgetc()</a></i>
could also be used.
</blockquote><h4><a name = "tag_000_005_450">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_005_451">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="fgetc.html">fgetc()</a></i>,
<i><a href="stdio.h.html">&lt;stdio.h&gt;</a></i>.
</blockquote><h4>DERIVATION</h4><blockquote>
Derived from Issue 1 of the SVID.
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
<br> [ <a href="../index.html">Main Index</a> | <a href="../xshix.html">XSH</a> | <a href="../xcuix.html">XCU</a> | <a href="../xbdix.html">XBD</a> | <a href="../cursesix.html">XCURSES</a> | <a href="../xnsix.html">XNS</a> ]

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